blob: 8f9f548411233060fe1c67d92314cd98ab7c7de6 [file] [log] [blame] [edit]
/*
* Just-In-Time compiler for BPF filters on MIPS
*
* Copyright (c) 2014 Imagination Technologies Ltd.
* Author: Markos Chandras <markos.chandras@imgtec.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; version 2 of the License.
*/
#ifndef BPF_JIT_MIPS_OP_H
#define BPF_JIT_MIPS_OP_H
/* Registers used by JIT */
#define MIPS_R_ZERO 0
#define MIPS_R_V0 2
#define MIPS_R_A0 4
#define MIPS_R_A1 5
#define MIPS_R_T4 12
#define MIPS_R_T5 13
#define MIPS_R_T6 14
#define MIPS_R_T7 15
#define MIPS_R_S0 16
#define MIPS_R_S1 17
#define MIPS_R_S2 18
#define MIPS_R_S3 19
#define MIPS_R_S4 20
#define MIPS_R_S5 21
#define MIPS_R_S6 22
#define MIPS_R_S7 23
#define MIPS_R_SP 29
#define MIPS_R_RA 31
/* Conditional codes */
#define MIPS_COND_EQ 0x1
#define MIPS_COND_GE (0x1 << 1)
#define MIPS_COND_GT (0x1 << 2)
#define MIPS_COND_NE (0x1 << 3)
#define MIPS_COND_ALL (0x1 << 4)
/* Conditionals on X register or K immediate */
#define MIPS_COND_X (0x1 << 5)
#define MIPS_COND_K (0x1 << 6)
#define r_ret MIPS_R_V0
/*
* Use 2 scratch registers to avoid pipeline interlocks.
* There is no overhead during epilogue and prologue since
* any of the $s0-$s6 registers will only be preserved if
* they are going to actually be used.
*/
#define r_skb_hl MIPS_R_S0 /* skb header length */
#define r_skb_data MIPS_R_S1 /* skb actual data */
#define r_off MIPS_R_S2
#define r_A MIPS_R_S3
#define r_X MIPS_R_S4
#define r_skb MIPS_R_S5
#define r_M MIPS_R_S6
#define r_skb_len MIPS_R_S7
#define r_s0 MIPS_R_T4 /* scratch reg 1 */
#define r_s1 MIPS_R_T5 /* scratch reg 2 */
#define r_tmp_imm MIPS_R_T6 /* No need to preserve this */
#define r_tmp MIPS_R_T7 /* No need to preserve this */
#define r_zero MIPS_R_ZERO
#define r_sp MIPS_R_SP
#define r_ra MIPS_R_RA
#ifndef __ASSEMBLY__
/* Declare ASM helpers */
#define DECLARE_LOAD_FUNC(func) \
extern u8 func(unsigned long *skb, int offset); \
extern u8 func##_negative(unsigned long *skb, int offset); \
extern u8 func##_positive(unsigned long *skb, int offset)
DECLARE_LOAD_FUNC(sk_load_word);
DECLARE_LOAD_FUNC(sk_load_half);
DECLARE_LOAD_FUNC(sk_load_byte);
#endif
#endif /* BPF_JIT_MIPS_OP_H */